Special Weather Statement, NWS Gaylord, MI

Area Forecast Discussion
National Weather Service Gaylord MI
620 AM EDT Sun Jul 26 2020

.NEAR TERM...(Today through Tonight)
Issued at 328 AM EDT Sun Jul 26 2020

Impactful weather: Numerous showers and scattered thunderstorms.
There is a slight chance for a severe storm in the GTV Bay region
this afternoon and early this evening, with localized damaging wind
gusts being the primary threat. Also, locally heavy rainfall is also
possible.

Pattern synopsis and forecast:

Upper level ridging was flattening over the Great Lakes early this
morning, due to shortwave activity from the upper Mississippi valley
and nrn Plains working eastward, along and north of a cold front and
now more ill-defined pre-frontal trough in that region. This
shortwave activity was working with a 1-8-2.4" PWAT air mass in an
environment of waning instability, but MUCAPES still running several
hundred j/kg across eastern Lake Superior, to as much as 1-2k j/kg
back in Wisconsin, where the majority of the lightning/storms were
occurring. Here in nrn Michigan, we are still in the process of
moistening and destabilizing the atmosphere, especially in eastern
upper, ahead of the pre-frontal trough. Skies were increasing in
cloudiness there, while skies were still mostly clear in nrn lower.

The pre-frontal trough will work it's way through nrn lower today,
followed by the actual cold front that crosses late tonight. The air
mass will continue to moisten and destabilize ahead of these
features, and diurnal destabilization will lead to 800-1600j/kg,
greatest instability mainly across NW/far nrn lower/eastern upper
this afternoon and early this evening. Scattered to numerous showers
and storms are expected today and this evening with the pre-frontal
trough and favorable air mass, with no cap to prevent an earlier
convective development. 0-6km effective shear is a measly 25 knots
(30kts around the GTV Bay region), so storms are not expected to
be too organized. Also, WBZ heights are way high to around 15kft
for the computed amount of instability to sustain a strong enough
updraft for a large hail threat. However, the large PWATs can lead
to locally heavy rainfall and possible microbursts with localized
damaging winds. There is a marginal threat for the localized
damaging winds sneaking into the GTV Bay region for this afternoon
and early evening (maybe due to the slightly better effective
shear, and this will be highlighted in the HWOAPX.

The instability wanes through the night while the cold front crosses
late tonight. There will still be additional showers anticipated,
but the thunder strength and severe threat will diminish. Behind the
front, sfc dew points will be on the way down with less humid and
not as warm weather anticipated through the day Monday (more on that
below).

Highs today will range from the middle 80s in eastern upper, to the
lower 90s across much of NE lower. Lows tonight will range from the
lower half of the 60s in western Chip/Mack counties, to the upper
60s to lower 70s in nrn lower.

&&

.SHORT TERM...(Monday through Tuesday)
Issued at 328 AM EDT Sun Jul 26 2020

...Heat and Humidity Abating...

High Impact Weather Potential...Low to Moderate.

Forecast Concerns...Heavy rainfall possible Monday.

The surface cold front will continue to progress across northeast
lower in the morning likely resulting in more showers and possibly a
thunderstorm or two across portions of northern lower. The potential
for heavy rainfall continues as precipitable water values start off
the day between 1.5 and 2 inches before diminishing to about 0.75
inches by late in the day. Drier air filters into eastern upper in
the morning and eventually into northern lower by mid to late
afternoon. Moisture then increases a little after that as an upper
level trough across northeast Ontario drops slowly southeast. This
will lead to small chances for a few instability driven showers
Tuesday afternoon and evening. Turning cooler and less humid Monday
with highs ranging from the upper 70s north to the mid 80s
northeast. Highs Tuesday ranging from the mid 70s to low 80s. Lows
Monday night mainly in the cooler mid and upper 50s.

.LONG TERM...(Tuesday night through Saturday)
Issued at 328 AM EDT Sun Jul 26 2020

...Seasonal Temperatures...

High Impact Weather Potential...Low.

The upper level trough will continue to linger off to our northeast
through Wednesday. This will lead to a slight chance for a couple
instability driven showers Wednesday (pm and eve). Upper level
ridging then establishes itself across the region for the remainder
of the period which is expected to result in rain-free
conditions. Temperatures will be near seasonal late July levels
then likely warm to a few degrees above normal to start off
August.

&&

.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
Issued at 618 AM EDT Sun Jul 26 2020

Warmer and more humid air continues to fill into nrn Michigan, ahead
of sfc troughing that crosses today, which will be followed by a
cold front late tonight into Monday. This will result in scattered
to numerous showers and thunderstorms over the TAF period. VSBY
restrictions will come with heavier periods of precipitation, and
skies will be increasing in cloudiness, with CIGS potentially
dropping to MVFR today through tonight with some areas of IFR late
tonight.

SW winds ahead of the low level troughing are likely to be gusty
today, with directions switching to out of the NW late tonight for
PLN/TVC/MBL.

&&

.MARINE...
Issued at 328 AM EDT Sun Jul 26 2020

Warmer and more humid air continues to fill into nrn Michigan, ahead
of sfc troughing that crosses today, which will be followed by a
cold front late tonight into Monday. This will result in scattered
to numerous showers and thunderstorms, which will depart eastern
upper and Lake Michigan Monday morning, and Lake Huron by Monday
evening. Severe storms are not expected.

Could be a few low end advisory SW wind gusts through daybreak, but
slightly stable conditions over the Great Lakes will keep speeds in
check. Winds will back from out of the SW to out of the NW, late
tonight into Monday as the cold front crosses. with no further
threat of advisory level wind speeds.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&

NEAR TERM...SMD
SHORT TERM...AS
LONG TERM...AS
AVIATION...SMD
MARINE...SMD

Hazardous Weather Outlook...CORRECTED
National Weather Service Gaylord MI
500 AM EDT Sun Jul 26 2020

MIZ016>018-020>036-041-042-086>088-095>099-270815-
Emmet-Cheboygan-Presque Isle-Leelanau-Antrim-Otsego-Montmorency-
Alpena-Benzie-Grand Traverse-Kalkaska-Crawford-Oscoda-Alcona-
Manistee-Wexford-Missaukee-Roscommon-Ogemaw-Iosco-Gladwin-Arenac-
Western Chippewa-Central Chippewa-Southeast Chippewa-
Western Mackinac-Eastern Mackinac-
Mackinac Island/Bois Blanc Island-
Beaver Island and surrounding islands-Charlevoix-
500 AM EDT Sun Jul 26 2020

This hazardous weather outlook is for Eastern Upper Michigan and
Northern Lower Michigan.

.DAY ONE...Today and tonight.

Scattered showers and thunderstorms are expected, mainly this
afternoon and evening. A few storms may be severe, particularly
around the Grand Traverse Bay region, with damaging winds being
the primary threat. Locally heavy rain is also possible.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

Showers and isolated thunderstorms, possibly containing heavy
rainfall, are possible Monday across parts of northern lower
Michigan.

A slight chance of thunderstorms returns Tuesday afternoon.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report any significant weather and
rainfall amounts to the National Weather Service. Reports may be
made one of three ways:

Online:   weather.gov/gaylord
Facebook: facebook.com/nwsgaylord

Twitter:  twitter.com/nwsgaylord

&&

For more information visit http://weather.gov/gaylord.

LHZ345>349-LMZ323-341-342-344>346-LSZ321-322-270815-
Straits of Mackinac within 5 nm of Mackinac Bridge including
Mackinac Island-St Ignace to False Detour Channel-
5NM East of Mackinac Bridge to Presque Isle Light MI including
Bois Blanc Island-
Presque Isle Light to Sturgeon Pt MI Including Thunder Bay
National Marine Sanctuary-Sturgeon Pt to Alabaster MI-
Grand Traverse Bay south of a line Grand Traverse Light to
Norwood MI-Seul Choix Point to 5NM West of Mackinac Bridge-
Norwood MI to 5NM West of Mackinac Bridge including Little
Traverse Bay-Sleeping Bear Point to Grand Traverse Light MI-
Point Betsie to Sleeping Bear Point MI-
Manistee to Point Betsie MI-
Whitefish Bay (U.S. Portion)/Whitefish Point to Point Iroquois MI-
St. Marys River Point Iroquois to E. Potagannissing Bay-
500 AM EDT Sun Jul 26 2020

This hazardous weather outlook is for the northern Michigan
nearshore waters of Lake Huron, Lake Michigan and Lake Superior.

.DAY ONE...Today and tonight.

Scattered showers and thunderstorms are expected, mainly this
afternoon and evening. A few storms may be severe with damaging
winds being the primary threat, in portions of Grand Traverse Bay
and the nearshore waters south of the Manitou Islands.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

Showers and isolated thunderstorms, possibly containing heavy
rainfall, are possible Monday across parts of northern lower
Michigan.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated.

&&

For more information visit http://weather.gov/gaylord.

Special Weather Statement
National Weather Service Gaylord MI
649 AM EDT Sun Jul 26 2020

MIZ086-095-096-261130-
Western Chippewa-Eastern Mackinac-Western Mackinac-
649 AM EDT Sun Jul 26 2020

...A STRONG THUNDERSTORM WILL AFFECT WEST CENTRAL CHIPPEWA AND
NORTHWESTERN MACKINAC COUNTIES...

At 648 AM EDT, a strong thunderstorm was located over Naubinway, or
15 miles south of Newberry, moving east at 30 mph.

Winds in excess of 30 mph are possible with this storm.

Locations impacted include...
St. Ignace, Moran, Brevort, Trout Lake, Epoufette, Garnet, Evergreen
Shores, Naubinway, Gilchrist, Allenville, Engadine, Fibre, Rexton,
East Lake and Garfield Township.

Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

LAT...LON 4637 8473 4589 8473 4592 8498 4598 8505
      4601 8516 4601 8523 4605 8533 4604 8546
      4605 8549 4599 8559 4625 8558 4625 8524
      4630 8524
TIME...MOT...LOC 1048Z 264DEG 28KT 4613 8543

Cornish